This invention relates to a drop gate for a particulate material tub or trough, and more particularly to a drop gate for a mixer as for animal feed.
Mixing of particulate material such as animal feed is conventionally performed as in a rotating ribbon mixer having an elongated housing tub or trough. At the curved bottom of the tub is a pair of hinged arcuate swing gates which swing downwardly open and away from each other on hinges along the outer edges of the gates, and along the edges of an opening, somewhat similar to bomb bay doors on an airplane. One of the gates typically has an elongated batten strip protruding from and extending along the inner edge of the gate, to underlie and overlap the juncture between the two arcuate gates when closed. The gates are conventionally closed by pivotal links and attached turnbuckles which are shifted upwardly in a compressive movement of the links and turnbuckles to close the gates. Such a prior art structure (see FIG. 11) has certain problems. One problem is the tendency for the gates not to close completely, often due to some of the feed material being caught between the adjacent, inner edges of the gates, and also between the batten strip and the adjacent gate. This can result in excess stress being applied to the turnbuckles when the gates are closed, too often causing the turnbuckles to bend or be otherwise damaged. This also results in the gates not closing tightly thereafter, i.e., at future operation thereof. Related to this problem is the tendency for the particulate material to get wedged not only between the two gates as noted above, but also between the outer edge of each gate and the edge of the adjoining tub on which the gate is hingedly mounted. For these and other reasons, the gates soon begin to leak material prior to dumping.
Another problem of the conventional structure is the tendency for the two gates to close out of synchronism such that the gate with the batten strip might close first and prevent the other gate from properly closing. Additional problems involve difficulty of replacement of the hinges when the hinge components become worn.